(i) Field of the Invention
The present invention relates to a component feeding method, a component feeding apparatus, and a component feeding unit, which are useful for taking out a forefront electronic component of electronic components such as chip components transferred in alignment.
(ii) Description of the Related Art
Japanese Patent Publication No. H1-183200 discloses an apparatus for transferring chip components by air suction force. The apparatus has a tubular feed path, an opening for taking out a component, which is provided at an end portion of the feed path, a stopper pin for positioning the forefront chip component at the opening, an air suction hole provided at a position spaced forward from the forefront chip component which came into contact with the stopper pin, and a shutter for opening and closing the opening.
The apparatus makes it possible to transfer chip components in the feed path forward by sucking air from a front side of the feed path with the opening being closed by the shutter and to allow the forefront chip component to come into contact with the stopper pin. The forefront chip component is taken out from the opening by a suction nozzle after the air suction is stopped and the shutter is moved to open the opening.
In the aforementioned apparatus, when the chip components in the feed path are transferred forward by air suction, a number of chip components are lined up in a pressed state after the forefront chip component abutting against the stopper pin, and under the influence thereof, the forefront chip component is in a state in which it is pressed forward by the following chip components. As a result, when the forefront chip component is taken out by the suction nozzle, there arise the disadvantage that the posture of the forefront chip component is disturbed and the disadvantage that the forefront chip component cannot be taken out. These disadvantages also occur in the same manner when the chip components in the feed path are transferred forward by blowing air from a rear side of the feed path.
The aforementioned disadvantages are considered to be eliminated by adopting the stopper pin movable forward and backward as the aforementioned stopper pin and advancing the stopper pin by a predetermined distance at the step before the forefront chip component is taken out, but only advancing the stopper pin a little cannot eliminate the aforementioned disadvantages. In order to eliminate the above-described disadvantages, it is necessary to advance the stopper pin to a large extent up to the position where the pressure force exerted on the forefront chip component can be eliminated, but since the pressure force exerted on the forefront chip component is not constant at each component transfer, the advancing distance of the forefront chip component when the stopper pin is advanced cannot be controlled, and as a result, the position of the forefront chip component varies, which makes it difficult to take out the forefront chip component by the suction nozzle.
An object of the present invention is to provide a component feeding method, a component feeding apparatus and component feeding unit, which can take out the forefront electronic component in a favorable condition without causing a poor posture after electronic components are transferred in alignment.
In order to achieve this object, the feeding method of the present invention is a component feeding method for transferring electronic components forward in alignment along a transfer passage such that the forefront electronic component abuts against a component stopper in order to take the forefront electronic component outside through a component ejection port, and when the forefront electronic component is taken outside through the component ejection port, air pressure for relieving pressing force is exerted rearward on at least one of the following electric components.
According to this component feeding method, when the forefront electronic component is taken outside through the component ejection port, air pressure for relieving pressing force is exerted rearward on at least one of the following electronic components, whereby the pressing force exerted on the forefront electronic component abutting against the component stopper from the following electronic components can be relieved. Consequently, the disadvantage that the posture of the forefront chip component is disturbed when the forefront chip component is taken out by the suction nozzle, and the disadvantage that the forefront chip component cannot be taken out can be eliminated.
The component feeding apparatus of the present invention is a component feeding apparatus including a transfer passage for transferring electronic components forward in alignment, a component stopper against which the forefront electronic component abuts, and a component ejection port for taking the forefront electronic component outside, and includes an air hole for exerting air pressure for relieving pressing force rearward on at least one of following electric components when the forefront electronic component is taken outside through the component ejection port.
According to this component feeding apparatus, when the forefront electronic component is taken outside, the air pressure is exerted rearward on at least one of the following electronic components through the air hole for relieving pressing force, whereby the aforementioned component feeding method can be carried out properly.
The component feeding unit of the present invention includes a component guide having a linear channel for a transfer passage, a cover for covering a top surface of a part where the linear channel of the component guide is formed except for a front portion by which a component ejection port from which an forefront electronic component is taken outside is constituted, a component stopper movable to a component stop position in contact with a front end surface of the linear channel and to a separation position away from the component stop position, a shutter movable to a component ejection port closed position at which the component ejection port is covered and to a component ejection port open position away from the component ejection port closed position, a first air hole for transferring electronic components, formed forward from the front end of said linear channel and communicating with a transfer passage, and a second air hole for relieving pressing force, formed rearward from the front end of said linear channel and communicating with the transfer passage.
According to this component feeding unit, the unitized mechanism part can be separately assembled, and therefore the aforementioned feeding apparatus can be easily assembled. The unitized mechanism part can be removed from the feeding apparatus and replaced with other one, and therefore maintenance can be facilitated. Further, only the unitized mechanism part can be on the market.
The aforementioned object, other objects, features and advantages of the present invention will become apparent upon reading the following explanation and the accompanying drawings.